Add new webkitgtk build as workaround for file conflict issue

The file conflict between older webkit2gtk4.1-jsc and new
javascriptcoregtk4.1 is causing all Workstation update tests to
fail on all Rawhide updates. This new version of webkitgtk adds
obsoletes to javascriptcoregtk4.1 which we hope should fix it.
Adding the x86_64 build directly as other arches aren't done
yet, and we only run the Workstation update tests on x86_64
anyway.

Signed-off-by: Adam Williamson <awilliam@redhat.com>

lib/utils.pm

@@ -482,7 +482,7 @@ sub setup_workaround_repo {
         "34" => [],
         "35" => [],
         "36" => [],
-        "37" => []
+        "37" => ["90614839"]
     );
     # then we'll download each update for our release:
     my $advortasks = $workarounds{$version};